Mac – Enabling Italics, Underline on Emacs, Xterm and Putty

emacsescape-charactersputtyterminalxterm

I'm using a Ubuntu (11.04 Server Edition) virtual machine as my development environment. It doesn't have a desktop environment since I don't think its necessary and I want to keep it lightweight. I'm accessing it via SSH with PuTTY on Windows 7. I grew fond of Emacs 24 as an IDE but still want to use inside a terminal.

I successfully enabled the 256 color version of xterm to render Emacs 24 themes properly, however the terminal doesn't render comments in italics and classes/functions/methods underlined as it is declared on the theme code. I noticed that the bold font style works after enabling it in PuTTY.

I tried changing the Terminal-Type string in PuTTY to rxvt-unicode with no avail. I also tried other terminal emulators like SecureCRT and forks like PuTTYcyg and KiTTY since I noticed Putty doesn't display fonts in italics as a general font setting.

I also tried Vim and other systems with all this options and configurations and it didn't work.

Is there a way to achieve this? How?

Best Answer

Just an FYI: Anything libvte based supports bold, italics, underline and strikethrough. No other terminal engine supports all four. Application support is virtually zero though because the functionality is only a few months old and it'll be many many years before the escape sequences are accepted and standardized.

Related Solutions

Mac – PuTTY or xterm for Mac

I use iTerm on the Mac, as well as the standard Terminal app.

Configuring fonts for xterm, urxvt, emacs and others

It's an X logical font description, used mostly by pure-Xlib programs.

"9x15bold" is a convenience alias for a bitmap font that comes with X.org. It doesn't mean anything specific, there's simply a "fonts.alias" table that translates it to an XLFD:

! $Xorg: fonts.alias,v 1.3 2000/08/21 16:42:31 coskrey Exp $
fixed        -misc-fixed-medium-r-semicondensed--13-120-75-75-c-60-iso8859-1
variable     -*-helvetica-bold-r-normal-*-*-120-*-*-*-*-iso8859-1
5x7          -misc-fixed-medium-r-normal--7-70-75-75-c-50-iso8859-1
...
8x16         -sony-fixed-medium-r-normal--16-120-100-100-c-80-iso8859-1
9x15         -misc-fixed-medium-r-normal--15-140-75-75-c-90-iso8859-1
9x15bold     -misc-fixed-bold-r-normal--15-140-75-75-c-90-iso8859-1
10x20        -misc-fixed-medium-r-normal--20-200-75-75-c-100-iso8859-1
...

Xresources is the conventional way. Or at least, used to be. For example, one could set the font for one program with URxvt.font, or for everything with *font, and this would affect all programs – including even those run on a remote server. (X11 is a network protocol.)

Most newly-written programs use systems such as dconf in GNOME, which is fine, because they were written specifically for GNOME. Xterm, however, is desktop environment-agnostic, because – most importantly – it was created long before KDE and GNOME and Qt and GTK; it is part of the core X11 software suite. Thus it sticks to Xresources because it's simple and standard, with no dependencies on third-party libraries or services. (It has its disadvantages, of course, such as the lack of real-time reconfiguration.)
Xterm is a pure Xlib program and uses the font rendering provided by X11, while GNOME Terminal, being written with GTK, uses Freetype (via Pango).

However, recent versions of Xterm and URxvt include support for basic Freetype font rendering via Xft (has less features than Pango, e.g. lacks font fallback, but often is "good enough"). You can use it by adding these resources:
```
URxvt.font: xft:DejaVu Sans Mono:size=9

XTerm*faceName: DejaVu Sans Mono
XTerm*faceSize: 9
```
Font size is in points (not pixels).

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